CN113728458A - Binder composition for electrode, coating composition for electrode, electrode for electricity storage device, and electricity storage device - Google Patents

Binder composition for electrode, coating composition for electrode, electrode for electricity storage device, and electricity storage device Download PDF

Info

Publication number
CN113728458A
CN113728458A CN202080029593.8A CN202080029593A CN113728458A CN 113728458 A CN113728458 A CN 113728458A CN 202080029593 A CN202080029593 A CN 202080029593A CN 113728458 A CN113728458 A CN 113728458A
Authority
CN
China
Prior art keywords
electrode
mass
storage device
active material
coating liquid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202080029593.8A
Other languages
Chinese (zh)
Inventor
祖父江绫乃
渡边聪哉
齐藤恭辉
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DKS Co Ltd
Original Assignee
Dai Ichi Kogyo Seiyaku Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dai Ichi Kogyo Seiyaku Co Ltd filed Critical Dai Ichi Kogyo Seiyaku Co Ltd
Publication of CN113728458A publication Critical patent/CN113728458A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/04—Hybrid capacitors
    • H01G11/06—Hybrid capacitors with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H01G11/30—Electrodes characterised by their material
    • H01G11/32—Carbon-based
    • H01G11/38—Carbon pastes or blends; Binders or additives therein
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being polymers
    • H01M4/623—Binders being polymers fluorinated polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H01G11/30—Electrodes characterised by their material
    • H01G11/32—Carbon-based
    • H01G11/36—Nanostructures, e.g. nanofibres, nanotubes or fullerenes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/84—Processes for the manufacture of hybrid or EDL capacitors, or components thereof
    • H01G11/86—Processes for the manufacture of hybrid or EDL capacitors, or components thereof specially adapted for electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Power Engineering (AREA)
  • Materials Engineering (AREA)
  • Electrochemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Manufacturing & Machinery (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Nanotechnology (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Electric Double-Layer Capacitors Or The Like (AREA)

Abstract

The invention provides a binder composition for an electrode, which can obtain an electrode exhibiting high durability even when an active material having a large volume change is used, an electrode for an electric storage device using the binder composition, and an electric storage device including the electrode for an electric storage device. A binder composition for an electrode, comprising at least one or two or more polymers selected from the group consisting of (A) a fluorine-based polymer, a butadiene-based polymer, and a thermoplastic elastomer, (B) a fibrous nanocarbon material having an average fiber diameter of 0.5nm to 20nm and a fiber length of 0.5 μm to 1mm, (C) a cellulose material, (D) a nanocellulose fiber, and (E) water, wherein the mass ratio of (A) to (B) is (A)/(B) from 60/40 to 98/2.

Description

Binder composition for electrode, coating composition for electrode, electrode for electricity storage device, and electricity storage device
Technical Field
The present invention relates to a binder composition for an electrode, a coating composition for an electrode using the binder composition for an electrode, an electrode for an electric storage device using the coating composition, and an electric storage device including the electrode.
Background
In recent years, a power storage device having a high voltage and a high energy density has been required as a driving power source for electronic equipment. In particular, lithium ion secondary batteries, lithium ion capacitors, and the like are expected as high-voltage and high-energy-density power storage devices. Such an electrode used in a power storage device is generally manufactured by applying and drying a mixture of electrode active material particles, conductive material particles, and a binder to the surface of a current collector. Examples of the power storage device include: lithium ion secondary batteries, electric double layer capacitors, lithium ion capacitors, and the like. These power storage devices are mainly composed of components such as electrodes, nonaqueous electrolyte, and separators.
Among these, the electrode for the power storage device is formed by, for example, applying an electrode mixture liquid for the power storage device, which is obtained by dispersing an electrode active material and a conductive material together with a binder in an organic solvent or water, onto a metal foil serving as a current collector surface, and drying the applied liquid. The characteristics of the power storage device are greatly influenced by the main constituent materials used, such as the electrode particulate material, the electrolyte, and the current collector, but are also greatly influenced by the binder, the thickening stabilizer, and the dispersant used as additives.
In particular, in the case of an electrode, a binder that imparts adhesion to an electrode active material, a current collector, and a space therebetween has a large influence on characteristics. For example, since the amount and type of the active material used determine the amount of lithium ions that can be bound to the active material, a battery with a high capacity can be obtained as the amount of the active material increases and as the intrinsic capacity of the active material used increases. Further, if the binder has excellent adhesion between the active materials and the current collector, electrons and lithium ions smoothly move in the electrode, and the internal resistance of the electrode is reduced, so that efficient charge and discharge can be performed. In addition, in the case of a high-capacity battery, a composite electrode of carbon and graphite, carbon and silicon is required as an anode active material, and the volume of the active material is greatly expanded and contracted during charge and discharge, so that the binder has not only excellent adhesion but also excellent elasticity, and it is necessary to maintain the original adhesion and restoring force even if the electrode volume is repeatedly expanded and contracted considerably. Further, in order to maintain the electron conduction path even when the volume of the electrode changes, it is preferable to uniformly disperse the conductive agent.
When an active material containing Si and having a large volume change is used, an example of using an acrylic polymer as shown in patent document 1 as a binder is disclosed. In general, electrodes using these high-strength binders have a feature that the electrodes do not break even if the volume of the active material changes, but it is difficult to maintain the flexibility of the electrodes, and there is a problem that peeling or the like is likely to occur during electrode processing. In addition, in general, dispersibility and rheology control of the electrode material are difficult to achieve only with acrylic polymers.
Documents of the prior art
Patent document
Patent document 1: international publication No. 2015/163302
Disclosure of Invention
Technical problem to be solved by the invention
The purpose of the present invention is to provide a binder composition for an electrode, which can provide an electrode exhibiting high durability even when an active material having a large volume change is used, a coating composition for an electrode using the composition, an electrode for an electrical storage device using the composition, and an electrical storage device provided with the electrode for an electrical storage device.
Means for solving the problems
The present inventors have made extensive studies to achieve the above object. In the course of this study, attention was focused on a combination of a polymer component and a fibrous nanocarbon material that satisfy predetermined requirements, and it was found that a desired problem can be solved by combining the polymer component and the fibrous nanocarbon material at a certain ratio, and the present invention has been completed.
The present invention provides the following [1] to [6 ].
[1] A binder composition for an electrode, characterized by comprising: (A) one or two or more polymer components selected from the group consisting of a fluorine-based polymer, a butadiene-based polymer and a thermoplastic elastomer, (B) a fibrous nanocarbon material having an average fiber diameter of 0.5nm or more and 20nm or less and an average fiber length of 0.5 μm or more and 1mm or less, (C) a cellulose material, (D) a nanocellulose fiber and (E) water, wherein the mass ratio of the component (a) to the component (B) is (a)/(B) 60/40 to 98/2.
[2] The binder composition for an electrode according to [1], wherein the mass ratio of the component (C) to the component (D) is (C)/(D) 30/70 to 98/2.
[3] The electrode coating liquid composition according to [1] or [2], wherein the cellulose material as the component (C) has a 2% by mass aqueous solution viscosity (at 25 ℃) of 500 mPas or less.
[4] A coating liquid composition for an electrode, comprising the binder composition for an electrode according to any one of claims 1 to 3, an active material and a dispersant, wherein the component (A) is 0.1 mass% or more and 10 mass% or less based on the solid content of the electrode coating liquid composition, the component (B) is 0.06 mass% or more and 2 mass% or less based on the solid content of the electrode coating liquid composition, and the component (C) is 0.06 mass% or more and 3 mass% or less based on the solid content of the electrode coating liquid composition.
[5] An electrode for an electric storage device, characterized by being produced using the coating liquid composition for an electrode according to [4 ].
[6] An electricity storage device comprising the electricity storage device backup electrode of [5 ].
Effects of the invention
Since the binder composition for an electrode of the present invention has flexibility and a capability of following a volume change, an electrode using the binder composition for an electrode of the present invention has a characteristic of being less likely to be peeled off during processing, and the resulting electricity storage device has high discharge performance and cycle stability. In addition, the electrode coating liquid composition using the binder composition for an electrode of the present invention has high dispersion stability and excellent rheology controllability.
Detailed Description
Next, embodiments of the present invention will be described in detail.
The binder composition for an electrode of the present invention contains at least (A) one or two or more polymer components selected from the group consisting of a fluorine-based polymer, a butadiene-based polymer, and a thermoplastic elastomer, (B) carbon nanotubes having an average fiber diameter of 0.5nm to 20nm and a fiber length of 0.5 μm to 1mm, (C) a cellulose material, (D) a nanocellulose fiber, and (E) water.
As one or two or more polymer components selected from the group consisting of the fluorine-based polymer, the butadiene-based polymer, and the thermoplastic elastomer, for example, there can be used: examples of the thermoplastic elastomer include, but are not limited to, polyvinylidene fluoride copolymer resins such as polyvinylidene fluoride, copolymers of polyvinylidene fluoride with hexafluoropropylene, perfluoromethylvinylether, and tetrafluoroethylene, fluorine-based polymers such as polytetrafluoroethylene and fluororubber, butadiene-based polymers such as styrene-butadiene rubber, ethylene-propylene rubber, and styrene-acrylonitrile copolymer, and thermoplastic elastomers such as polyurethane resins, polyester resins, polyimide resins, polyamide resins, and epoxy resins. These polymer components may be used alone or in combination of two or more, or two or more resin composite types may be used. These polymer components are preferably water-soluble and/or water-dispersible high molecular compounds.
(B) Fibrous nanocarbon material
The fibrous nanocarbon material is characterized by being composed of a fibrous nanocarbon material having an average fiber diameter of 0.5nm to 20nm inclusive and an average fiber length of 0.5 μm to 1mm inclusive. When the average fiber diameter is less than 0.5nm, the viscosity of a dispersion of a fibrous nanocarbon material described later becomes too high, and therefore, it may be difficult to prepare a coating composition for an electrode, and when the average fiber diameter exceeds 20nm, the flexibility of the fibrous nanocarbon material decreases, and therefore, the durability of the prepared electrode composite material layer decreases, and the cycle characteristics when the electrode composite material layer is produced into a battery may decrease. When the fiber length is less than 0.5 μm, the resulting electrode composite layer may not be sufficiently durable, and the cycle life of the resulting battery may be reduced. If the fiber length exceeds 1mm, it may be difficult to control the rheology of the dispersion of the fibrous nanocarbon material. The average fiber length and the average fiber width can be measured, for example, by measuring the major axis diameter of 100 fibrous nanocarbon materials randomly selected from a transmission electron micrograph and a scanning probe-type micrograph, and calculating the number average particle diameter calculated as the arithmetic mean of the major axis diameters. Examples of the fibrous nanocarbon material include single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs), and SWCNTs can be preferably used in consideration of the effect on the amount added. As the component (B), 1 or more of the above-mentioned compounds may be used alone, or 2 or more of them may be used in combination.
The fibrous nanocarbon material is preferably used in a state of being dispersed in a predetermined medium. The dispersion is prepared by dispersing a fibrous nanocarbon material as a raw material in a medium to a nano size by a known method. As the medium, water is usually used, but a polar solvent such as alcohol or ketone solvent, or a mixed solvent of these polar organic solvents and water may be used.
The fibrous nanocarbon material dispersion can be obtained more efficiently by adding the cellulose material as the component (C) and the nanocellulose fiber as the component (D) as the dispersant and the rheology control agent.
As examples of the cellulose material, celluloses such as hydroxymethyl cellulose, carboxymethyl cellulose and alkali metal salts thereof, methyl cellulose, ethyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl methyl cellulose, and the like can be used. Among them, sodium salt of carboxymethyl cellulose is particularly preferably used. As examples of the nano cellulose fibers, cellulose nano fibers described in japanese patent No. 5626828 and japanese patent No. 5921960 can be particularly preferably used. Examples of the apparatus for producing the fibrous nanocarbon material dispersion include a jet mill, a high-pressure dispersing apparatus, and an ultrasonic homogenizer.
The carboxymethyl cellulose salt having a low viscosity is preferably used because it can impart more excellent dispersibility when combined with the above-mentioned nanocellulose fibers, facilitates the rheology control, and improves the function of the fibrous nanocarbon. Specifically, the viscosity of a 2 mass% aqueous solution of the carboxymethyl cellulose salt is preferably 500 mPas or less, and more preferably 100 mPas or less. The lower limit of the viscosity of the 1% by mass aqueous solution may be, for example, 5 mPas or more.
Here, the viscosity of a 2 mass% aqueous solution of the carboxymethyl cellulose salt was measured as follows. That is, a carboxymethyl cellulose salt (about 4.4g) was placed in a stoppered 300ml Erlenmeyer flask for accurate weighing. Here, water was added in an amount calculated from the calculation formula "sample (g) × (98-water content (% by mass)/2)", and the mixture was left for 12 hours and further mixed for 5 minutes. The resulting solution was measured for viscosity at 25 ℃ using a single cylinder type rotational viscometer in accordance with JIS Z8803.
The mass ratio of the cellulose material (C) to the nanocellulose fiber (D) is preferably (C)/(D) 30/70 to 98/2, and more preferably 50/50 to 90/10. When the mass ratio is less than 30/70, the viscosity and thixotropy of the fibrous nanocarbon material dispersion become too high, and therefore, the coating control of the coating composition for electrodes may become difficult, and when the mass ratio exceeds 90/10, the dispersibility of the fibrous nanocarbon material may decrease.
In the binder composition for an electrode of the present invention, the mass ratio of the polymer component (a) to the fibrous nanocarbon material (B) is (a)/(B) 60/40 to 98/2. When the mass ratio is less than 60/40, the flexibility and adhesiveness of the electrode composite material layer may be reduced, and the viscosity of the coating liquid composition for an electrode may be extremely high, which may cause a problem in forming an electrode. When the mass ratio exceeds 98/2, the adhesion of the electrode composite material layer may be reduced, and the resistance of the electrode may be increased, thereby possibly resulting in a reduction in battery characteristics.
The total amount of the cellulose material (C) and the nanocellulose fibers (D) added to the fibrous nanocarbon material is preferably 5 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the fibrous nanocarbon. Within the above-mentioned addition amount range, the dispersibility and dispersion stability of the fibrous nanocarbon material are improved, and the viscosity of the electrode coating composition for producing an electrode can be appropriately adjusted, thereby facilitating the production of an electrode.
The electrode coating liquid composition of the present invention contains the binder composition for an electrode, an active material, a conductive auxiliary agent, and a dispersant, which will be described later. In the electrode coating liquid composition of the present invention, the polymer component (a) is preferably 0.1 mass% or more and 10 mass% or less with respect to the solid content of the electrode coating liquid composition. When the polymer component (a) is in the above range, the advantage of being able to achieve both the adhesiveness of the electrode composite material layer and the electron conductivity of the electrode is obtained. The fibrous nanocarbon material (B) is preferably 0.06% by mass or more and 2% by mass or less based on the solid content of the electrode coating liquid composition. When the content of the fibrous nanocarbon material (B) is within the above range, there is an advantage that the rheological properties of the electrode coating liquid composition, the adhesion of the electrode composite material layer, and the electron conductivity of the electrode can be satisfied at the same time. Further, (C) the cellulose material is preferably 0.06 mass% or more and 3 mass% or less with respect to the solid content of the electrode coating liquid composition. When the content of the cellulose material (C) is within the above range, there is an advantage that both rheological properties of the electrode coating liquid composition and electron conductivity of the electrode can be satisfied. The total amount of the dispersant and the binder composition for an electrode is preferably 0.5 mass% or more and 10 mass% or less with respect to the solid content of the electrode coating liquid composition. Although it depends on the nature of the active material used, in general, when the content is in the above range, an electrode coating liquid composition having excellent dispersibility of the active material and the conductive assistant and appropriate thixotropy can be obtained. The content is preferably 1 mass% or more, and more preferably 1.5 mass% or more. Further, it is preferably 8% by mass or less, and more preferably 5% by mass or less.
In the coating liquid composition for an electrode of the present invention, a dispersant may be added independently from the above-mentioned component (C) and component (D) within a range not to impair the effects of the present invention. The dispersant preferably contains one or more additives having a dispersing function. The additive having the dispersing function is not particularly limited, and may be selected from 1 or 2 or more of the following additives: celluloses such as hydroxymethyl cellulose, carboxymethyl cellulose and alkali metal salts thereof, methyl cellulose, ethyl cellulose, hydroxypropyl methyl cellulose, and hydroxyethyl methyl cellulose; cellulose nanofibers such as chemically modified cellulose nanofibers described in japanese patent No. 5626828 and japanese patent No. 5921960; polycarboxylic acid compounds such as polyacrylic acid and sodium polyacrylate; compounds having a vinylpyrrolidone structure such as polyvinylpyrrolidone; polyurethane resin, polyester resin, polyacrylamide, polyethylene oxide, polyvinyl alcohol, sodium alginate, xanthan gum, carrageenan, guar gum, agar, starch and the like. Among them, carboxymethyl cellulose salt is preferably used.
In the coating liquid composition for an electrode of the present invention, a conductive assistant may be added within a range not to impair the effects of the present invention. The conductive aid may be any electronically conductive material that does not adversely affect the battery performance. Normally, carbon black such as acetylene black or ketjen black is used, but may be a conductive material such as natural graphite (scale graphite, flake graphite, earthy graphite, etc.), artificial graphite, carbon whiskers, carbon fibers, metal (copper, nickel, aluminum, silver, gold, etc.) powder, metal fibers, conductive ceramic material, and the like. They may be used in a mixture of 1 or 2 or more. The amount of the additive is preferably 0.1 to 30 wt%, particularly preferably 0.2 to 20 wt%, based on the amount of the active material. The fibrous nanocarbon material as a component of the binder composition of the present invention can also function as a conductive aid.
In the coating liquid composition for an electrode of an electric storage device of the present invention, the method, the order, and the like of mixing the electrode materials are not particularly limited, and for example, a conductive auxiliary agent, a dispersant, and a binder composition may be mixed in advance and used. The mixing and dispersing device used for the mixing and dispersing treatment of the composition is not particularly limited, and examples thereof include a homogenizer, a planetary mixer, a propeller mixer, a kneader, a homogenizer, an ultrasonic homogenizer, a colloid mill, a bead mill, a sand mill, and a high-pressure homogenizer.
The power storage device of the present invention is not particularly limited, and known power storage devices may be used, and specifically, a lithium secondary battery, a lithium ion capacitor, and the like may be used.
The positive electrode active material used for the positive electrode of the lithium secondary battery is not particularly limited as long as it can insert and desorb lithium ions. Examples are: CuO, Cu2O、MnO2、MoO3、V2O5、CrO3、MoO3、Fe2O3、Ni2O3、CoO3Isometal oxide, LixCoO2、LixNiO2、LixMn2O4、LiFePO4Composite oxide of isolithium and transition metal, TiS2、MoS2、NbSe3Isometal chalcogenides, polyacenes,And conductive polymer compounds such as polyparaphenylene, polypyrrole, polyaniline, and the like.
Among the above, from the viewpoint of lithium ion releasing property and easy availability of high voltage, a composite oxide of lithium and 1 or more kinds selected from transition metals such as cobalt, nickel, and manganese, which are generally called high voltage system, is preferable. Specific examples of the composite oxide of cobalt, nickel, manganese and lithium include: LiCoO2、LiMnO2、LiMn2O4、LiNiO2、LiNixCo(1-x)O2、LiMnaNibCocAnd (a + b + c ═ 1).
Further, those obtained by doping these lithium composite oxides with a small amount of an element such as fluorine, boron, aluminum, chromium, zirconium, molybdenum, or iron, or those obtained by doping the particle surface of a lithium composite oxide with carbon, MgO, or Al may be used2O3、SiO2And the like which have been subjected to surface treatment. The positive electrode active material may be used in combination of 2 or more.
The negative electrode active material used for the negative electrode of the lithium secondary battery is not particularly limited as long as it can intercalate and deintercalate lithium metal or lithium ions, and a known active material can be used. For example, carbon materials such as natural graphite, artificial graphite, non-graphitizable carbon, and graphitizable carbon can be used. Further, metal materials such as metallic lithium, alloys, and tin compounds, lithium transition metal nitrides, crystalline metal oxides, amorphous metal oxides, silicon compounds, conductive polymers, and the like may be used, and specific examples thereof include Li4Ti5O12, NiSi5C6, and the like.
As the electric storage device of the present invention, for example, as an electrode active material used for an electrode for an electric double layer capacitor, an allotrope of carbon is generally used. Specific examples of carbon allotropes include: activated carbon, polyacene, carbon whisker, graphite, and the like, and powder or fiber thereof can be used. The electrode active material is preferably activated carbon, and specifically, activated carbon using a phenol resin, rayon, an acrylonitrile resin, pitch, coconut shell, or the like as a raw material is exemplified.
Among the electrode active materials used in the above-described electrode for a lithium ion capacitor, any electrode active material used in a positive electrode of an electrode for a lithium ion capacitor may be used as long as it can reversibly support lithium ions and anions such as tetrafluoroborate. Specifically, carbon allotropes are generally used, and electrode active materials used in electric double layer capacitors can be widely used.
The electrode active material used for the negative electrode of the electrode for a lithium ion capacitor is a material capable of reversibly supporting lithium ions. Specifically, an electrode active material used for a negative electrode of a lithium ion secondary battery can be widely used. Preferred examples thereof include crystalline carbon materials such as graphite and non-graphitizable carbon, and polyacene-based materials (PAS) also described as the positive electrode active material. As the carbon material and PAS, those obtained by carbonizing a phenol resin or the like, activating it as necessary, and then pulverizing them can be used.
The content of the electrode active material in the electrode coating liquid composition of the present invention is not particularly limited, and is 60 mass% or more and 97 mass% or less in 100 mass% of the total solid content.
As the current collector of the electrode active material used in the power storage device of the present invention, any current collector may be used as long as it is an electron conductor that does not adversely affect the battery to be configured. For example, as the current collector for the positive electrode, in addition to aluminum, titanium, stainless steel, nickel, calcined carbon, conductive polymer, conductive glass, or the like, a material obtained by treating the surface of aluminum, copper, or the like with carbon, nickel, titanium, silver, or the like, may be used for the purpose of improving adhesion, conductivity, and oxidation resistance. In addition, as the current collector for the negative electrode, in addition to copper, stainless steel, nickel, aluminum, titanium, calcined carbon, conductive polymer, conductive glass, Al — Cd alloy, and the like, a current collector obtained by treating the surface of copper or the like with carbon, nickel, titanium, silver, or the like may be used for the purpose of improving adhesiveness, conductivity, and oxidation resistance. The surface of these current collector materials may be subjected to oxidation treatment. In addition, as the shape, a film, a sheet, a net, a punched or expanded shape, a molded body such as a lath, a porous body, or a foam may be used in addition to the foil shape. The thickness is not particularly limited, and a thickness of 1 to 100 μm is usually used.
The electrode of the power storage device of the present invention can be produced, for example, by mixing an electrode active material, a conductive assistant, a collector of the electrode active material, a binder for binding the electrode active material and the conductive assistant to the collector, and the like to prepare a slurry-like electrode material, applying the electrode material to an aluminum foil, a copper foil, or the like serving as the collector, and volatilizing a dispersion medium.
The method, procedure, and the like of mixing the electrode material are not particularly limited, and for example, the active material and the conductive aid may be mixed in advance and used, and in this case, a mortar, a stirring mixer, a ball mill such as a planetary ball mill or a ball mill, mechanical fusion, or the like may be used for the mixing.
The separator used in the power storage device of the present invention is not particularly limited, and a separator used in a general power storage device can be used, and examples thereof include porous resins containing polyethylene, polypropylene, polyolefin, polytetrafluoroethylene, and the like, ceramics, nonwoven fabrics, and the like.
The electrolyte used in the power storage device of the present invention is not particularly limited as long as it is an electrolyte used in a normal power storage device, and a general electrolyte such as an organic electrolyte and an ionic liquid may be used. Examples of the electrolyte salt used in the power storage device of the present invention include: LiPF6、LiBF4、LiClO4、LiAsF6、LiCl、LiBr、LiCF3SO3、LiN(CF3SO2)2、LiC(CF3SO2)3、LiI、LiAlCl4、NaClO4、NaBF4And NaI, and the like, and particularly, there may be mentioned: LiPF6、LiBF4、LiClO4、LiAsF6Etc. inorganic lithium salt, LiN (SO)2CxF2x+1)(SO2CyF2y+1) The organic lithium salt shown. Wherein x and y represent 0 or an integer of 1 to 4, and x + y represents 2 to 8. As the organic lithium salt, specifically, there may be mentionedMention is made of: LiN (SO)2F)2、LiN(SO2CF3)(SO2C2F5)、LiN(SO2CF3)(SO2C3F7)、LiN(SO2CF3)(SO2C4F9)、LiN(SO2C2F5)2、LiN(SO2C2F5)(SO2C3F7)、LiN(SO2C2F5)(SO2C4F9) And the like. Wherein if LiPF is used6、LiBF4、LiN(CF3SO2)2、LiN(SO2F)2、LiN(SO2C2F5)2And the like are preferably used for the electrolyte because they are excellent in electrical characteristics. The electrolyte salt may be used in 1 kind, or 2 or more kinds. Such a lithium salt is usually contained in the electrolyte at a concentration of 0.1 to 2.0moL/L, preferably 0.3 to 1.5 moL/L.
The organic solvent used for dissolving the electrolyte salt used in the power storage device of the present invention is not particularly limited as long as it is an organic solvent used in the nonaqueous electrolytic solution of the power storage device, and examples thereof include: carbonate compounds, lactone compounds, ether compounds, sulfolane compounds, dioxolane compounds, ketone compounds, nitrile compounds, halogenated hydrocarbon compounds, and the like. Specifically, the following may be mentioned: carbonic acid esters such as dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, dimethyl ethylene carbonate, dimethyl propylene carbonate, diethyl ethylene carbonate and vinylene carbonate, lactones such as γ -butyrolactone, ethers such as dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran and 1, 4-dioxane, sulfolane such as sulfolane and 3-methylsulfolane, dioxolane such as 1, 3-dioxolane, ketones such as 4-methyl-2-pentanone, nitriles such as acetonitrile, propionitrile, valeronitrile and benzonitrile, halogenated hydrocarbons such as 1, 2-dichloroethane, and other plasma liquids such as methyl formate, dimethylformamide, diethylformamide, dimethyl sulfoxide, imidazolium salt and quaternary ammonium salt. Further, a mixture thereof is also possible. Among these organic solvents, a nonaqueous solvent containing at least one kind selected from the group consisting of carbonates is particularly preferable because it is excellent in solubility of an electrolyte, dielectric constant and viscosity.
In the case where the electric storage device of the present invention is used for a polymer electrolyte or a polymer gel electrolyte, examples of the polymer compound include a polymer having a polymer structure or a copolymer thereof such as ether, ester, siloxane, acrylonitrile, vinylidene fluoride, hexafluoropropylene, acrylate, methacrylate, styrene, vinyl acetate, vinyl chloride, and oxetane, and a crosslinked product thereof. The polymer structure is not particularly limited, and a polymer having an ether structure such as polyethylene oxide is particularly preferable. In addition, inorganic substances such as metal oxides may be used in combination. Examples of the metal oxide are not particularly limited as long as they are metal oxides used for the power storage device, and include: SiO2, Al2O3, AlOOH, MgO, CaO, ZrO2, TiO2, Li7La3Zr2O12, LixaLayaTiO3 [ xa ═ 0.3 to 0.7, ya ═ 0.3 to 0.7 ], BaTiO3, and the like.
In the electric storage device of the present invention, the liquid-type battery is a battery in which an electrolytic solution is contained in a battery container, the gel-type battery is a battery in which a precursor solution in which a polymer is dissolved in an electrolytic solution is contained in a battery container, and the solid-electrolyte battery is a battery in which a polymer in which an electrolyte salt is dissolved before crosslinking is contained in a battery container.
The power storage device of the present invention may be formed in any shape such as a cylindrical shape, a coin shape, a rectangular shape, a laminate shape, and others, and the basic configuration of the battery is the same regardless of the shape, and may be designed and modified according to the purpose. For example, in the cylindrical type, a negative electrode in which a negative electrode active material is applied to a negative electrode current collector and a positive electrode in which a positive electrode active material is applied to a positive electrode current collector are wound with a separator interposed therebetween are housed in a battery can, and a nonaqueous electrolytic solution is injected and sealed in a state in which an insulating plate is placed on top and bottom. When applied to a coin-type battery, the battery is housed in a coin-type battery can in a state in which a disk-shaped negative electrode, a separator, a disk-shaped positive electrode, and a stainless steel plate are stacked, and a nonaqueous electrolytic solution is injected and sealed.
Examples
Next, examples will be described together with comparative examples. However, the present invention is not limited to these examples. In the examples, "%" refers to mass basis unless otherwise specified.
Synthesis of Polymer component (aqueous resin emulsion)
Synthesis example 1-2 Synthesis of styrene butadiene rubber emulsion (SBR emulsion) A-1
51 parts by mass of preparation water and 0.2 part by mass of dodecylbenzenesulfonate were added to a flask equipped with a stirrer, a reflux condenser and a thermometer, and the temperature was raised to 40 ℃. Further, 5 parts by mass of acrylonitrile, 8 parts by mass of methyl methacrylate, 55 parts by mass of styrene, 32 parts by mass of 1, 3-butadiene, and 0.95 part by mass of an alkylbenzenesulfonate, which are components of the pre-emulsion, were separately emulsified and dispersed in 40 parts by mass of a water for preparation to prepare a pre-emulsion. This pre-emulsion was added dropwise from a dropping funnel to the flask over 4 hours, and 0.4 part by mass of a sodium persulfate initiator was added as a 10% aqueous solution as a polymerization initiator to start polymerization. And maintaining the reaction temperature of 65 ℃ for 4 hours, heating to 80 ℃, and continuing to react for 2 hours to obtain the SBR emulsion A-1.
[ production of fibrous nanocarbon Material Dispersion ]
Synthesis example 2-1 preparation of fibrous nanocarbon Material Dispersion B-1 (for example)
1.0g of SWCNT (TUBALL BATT manufactured by OCSIAL, CNT purity > 93%, average diameter 1.6. + -. 0.5nm), 45g of a 2 wt% aqueous solution of carboxymethyl cellulose salt (CELLOGEN 7A manufactured by first Industrial pharmaceutical Co., Ltd., viscosity of 2 wt% aqueous solution (25 ℃ C.): 12 to 18 mPas, C-1 in Table 2), and 5g of a 2 wt% aqueous solution of cellulose nanofibers (RHCRYSTA I-2SX-LDS manufactured by first Industrial pharmaceutical Co., Ltd., D-1 in Table 2) were mixed in a beaker and stirred, and then the slurry was dispersed at an output of 100uA for 90 minutes while being circulated by connecting a circulation unit and a tube pump manufactured by ultrasonic homogenizer US-600T Japan K.K..
Synthesis example 2-2 preparation of fibrous nanocarbon Material Dispersion B-2 (for example)
A fibrous nanocarbon material dispersion B-2 was prepared in accordance with Synthesis example 2-1, except that a 2 wt% aqueous solution of a carboxymethylcellulose salt (CELLOGEN 7A, first Industrial pharmaceutical Co., Ltd.) was changed to a 2 wt% aqueous solution of a carboxymethylcellulose salt (WS-C, C-2 in Table 2, first Industrial pharmaceutical Co., Ltd.).
Synthesis example 2-3 preparation of fibrous nanocarbon Material Dispersion B-3 (for example)
Fibrous nanocarbon material dispersion B-3 was prepared according to synthesis example 2-1, except that the treatment conditions of the ultrasonic homogenizer were changed to 100uA and 120 minutes.
Synthesis examples 2 to 4 preparation of fibrous nanocarbon material dispersion B' -1 (for comparative example)
Fibrous nanocarbon material dispersion B' -1 was prepared according to synthesis example 2-1, except that the treatment conditions of the ultrasonic homogenizer were changed to 200uA and 240 minutes.
Synthesis examples 2 to 5 preparation of fibrous nanocarbon Material Dispersion B' -2 (for example)
A fibrous nanocarbon material dispersion B' -2 was prepared in accordance with Synthesis example 2-1, except that 45g of a 2 wt% aqueous solution of the added carboxymethylcellulose salt (CELLOGEN 7A, first Industrial pharmaceutical Co., Ltd.) and 5g of a 2 wt% aqueous solution of the cellulose nanofibers (RHEOCRYSTA I-2SX-LDS, first Industrial pharmaceutical Co., Ltd.) were changed to 50g of the carboxymethylcellulose salt alone (CELLOGEN 7A, first Industrial pharmaceutical Co., Ltd.).
Synthesis examples 2 to 6 preparation of fibrous nanocarbon Material Dispersion B' -3 (for example)
A fibrous nanocarbon material dispersion B' -3 was prepared in accordance with Synthesis example 2-1, except that 45g of a 2 wt% aqueous solution of a carboxymethylcellulose salt (CELLOGEN 7A, first Industrial pharmaceutical Co., Ltd.) was changed to 10g, and 5g of a 2 wt% aqueous solution of cellulose nanofibers (RHEOCRYSTA I-2SX-LDS, first Industrial pharmaceutical Co., Ltd.) was changed to 40 g.
[ evaluation of fibrous nanocarbon material Dispersion ]
The average fiber width and the average fiber length of the fibrous nanocarbon material dispersion were observed using a Scanning Probe Microscope (SPM) (AFM-5300E, manufactured by Nippon electronics Co., Ltd.). That is, each fibrous nanocarbon dispersion was diluted to a solid content concentration of 0.01 wt%, cast on a mica substrate, and an AFM image of a dried sample was observed to calculate an average fiber width and an average fiber length according to the methods described above. Using these values, the aspect ratio was calculated according to the following formula 1.
Length-diameter ratio (average fiber length (nm)/average fiber width (nm) (formula 1)
The measurement results are shown in table 1. The fibrous nanocarbon material dispersions B-1 to B-3 used in the examples had an average fiber width in the range of 1 to 200nm and an average fiber length of 0.5 μm or more. In contrast, the average fiber length of the cellulose fibers B' -1 for the comparative examples was outside the above range.
[ Table 1]
B-1 B-2 B-3 B’-1 B’-2 B’-3
Average fiber width 3 4 2 2 4 5
Average fiber length 3200 3500 1500 400 2800 2200
Aspect ratio 1067 875 750 200 700 440
[ production of coated electrode ]
(cathode 1)
SiO (average particle diameter 4.5 μm, specific surface area 5.5 m) was used as a negative electrode active material2(g) and graphite (average particle diameter 18 μm, specific surface area 3.2 m)2(G) 95 parts (content ratio 20/80), 2 parts of acetylene black (manufactured by DENKA K.K., Li-400, F-1 in Table 2) as a conductive auxiliary agent, 0.8 parts of carboxymethyl cellulose salt (manufactured by first Industrial pharmaceutical Co., Ltd., WS-C, G-1 in Table 2) as a dispersant and binder, 2 parts (parts by solid content) of SBR emulsion A-1 (a-1 in Table 2) as a polymer component, and 10.2 parts (parts by solid content) of fibrous nanocarbon material dispersion B-10.2 were stirred by a homogenizer to prepare a negative electrode slurry so that the solid content became 40%. The negative electrode slurry was roll-coatedAn electrolytic copper foil having a thickness of 10 μm was coated with a coater (product name チビコーター (mini coater) manufactured by THANKMETAL), dried at 120 ℃, and then subjected to roll-pressing treatment to obtain 7 to 8mg/cm of a negative electrode active material2Negative electrode 1 of (1).
(cathode 2, 3)
The same procedure as for negative electrode 1 was carried out except that fibrous nanocarbon material dispersion B-1 was changed to B-2 and B-3 shown in table 1, respectively.
(cathode 4)
Except that SiO (average particle diameter 4.5 μm, specific surface area 5.5 m) was used as a negative electrode active material2(g) and graphite (average particle diameter 18 μm, specific surface area 3.2 m)2(g) was changed to 96 parts (content: 10/90), acetylene black as a conductive aid was changed to 1.5 parts, and SBR emulsion A-1 as a polymer component was changed to 1.5 parts (parts by solid content), and a negative electrode active material weight of 8 to 9mg/cm was prepared in the same manner as in the negative electrode 32And a negative electrode 4.
(cathode 5)
The negative electrode active material was changed to SiO (average particle diameter: 4.5 μm, specific surface area: 5.5 m)2(g) and graphite (average particle diameter 18 μm, specific surface area 3.2 m)292 parts (content: 30/70), a negative electrode active material weight of 5 to 6mg/cm was prepared in the same manner as in the negative electrode 3 except that acetylene black as a conductive auxiliary was changed to 2.5 parts, a carboxymethyl cellulose salt as a dispersant and binder was changed to 1.3 parts, and an SBR emulsion A-1 as a polymer component was changed to 4 parts (parts by solid matter) to prepare a negative electrode active material weight of 5 to 6mg/cm2And a negative electrode 5.
(cathode 6)
The negative electrode active material was changed to SiO (average particle diameter 7 μm, specific surface area 2.2 m)2(g) and graphite (average particle diameter 18 μm, specific surface area 3.2 m)2The negative electrode was produced in the same manner as in the negative electrode 3 except that 92 parts (content: 20/80), 1.8 parts of a carboxymethyl cellulose salt as a dispersant and binder, and 4 parts of an SBR emulsion a-1 as a polymer component (solid content) were used.
(cathode 7)
Except that the negative electrode is activatedThe material was changed to Si (average particle diameter 2.6 μm, specific surface area m)2(g) and graphite (average particle diameter 18 μm, specific surface area 3.2 m)294 parts (content: 10/90), and 5 to 6mg/cm in weight of the negative electrode active material was prepared in the same manner as for the negative electrode 3 except that the SBR emulsion A-1 as the polymer component was changed to 3 parts (solid content part)2And a negative electrode 7.
(cathode 8)
The negative electrode active material was changed to Si (average particle diameter 10nm, specific surface area m)2(g) and graphite (average particle diameter 18 μm, specific surface area 3.2 m)2(g) 93 parts (content: 10/90), a negative electrode active material weight of 5 to 6mg/cm was prepared in the same manner as in the negative electrode 3 except that acetylene black as a conductive auxiliary was changed to 2.3 parts, a carboxymethyl cellulose salt as a dispersant and binder was changed to 1.0 part, and an SBR emulsion A-1 as a polymer component was changed to 3.5 parts (parts by solid matter)2And a negative electrode 8.
(for comparative example)
(cathode 9)
The negative electrode active material was changed to SiO (average particle diameter: 4.5 μm, specific surface area: 5.5 m)2(g) and graphite (average particle diameter 18 μm, specific surface area 3.2 m)2And/g) 90.5 parts (content ratio 20/80), 1.3 parts of acetylene black as a conductive aid, 1.3 parts of a carboxymethyl cellulose salt as a dispersant and binder, and 6 parts of polyacrylic acid sodium salt a' -1 (molecular weight Mw 13 ten thousand) as 6 parts of SBR emulsion a-11.5 parts (parts by solid content) as a polymer component.
(cathode 10)
A fibrous nanocarbon material B-1 was produced in the same manner as in negative electrode 1, except that B' -1 shown in table 1 was used instead.
(cathode 11)
The negative electrode 10 was produced in the same manner as in the case of negative electrode 10 except that the fibrous nanocarbon material dispersion B' -1 was not used, acetylene black as a conductive additive was changed to 2.1 parts, and a carboxymethyl cellulose salt as a dispersant and a binder was changed to 0.9 part.
(cathode 12, 13)
The same method as in negative electrode 10 was used except that fibrous nanocarbon dispersion B ' -1 was changed to B ' -2 and B ' -3 shown in table 1, respectively.
(evaluation of physical Properties of coating composition)
(evaluation of viscosity and coatability)
The viscosity of each negative electrode slurry obtained as described above immediately after the production was measured with a rotational viscometer (product name: TVB-10M manufactured by eastern industries), and the viscosity value at the time point 2 minutes elapsed after the start of the measurement was read. (rotational speed at the time of evaluation: 6rpm) coating uniformity when the coating material obtained above was coated by a roll coater was evaluated according to the following criteria. The evaluation results are shown in table 2 below.
Evaluation criteria:
o: the coating material has a viscosity of 8000mPa or less and can be applied to a uniform film thickness
And (delta): the coating has a viscosity of 8000mPa or more and a non-uniform film thickness (streaks or the like)
X: the viscosity of the coating material is 8000mPa or more, and the coating material cannot be coated
[ conductivity of electrode ]
The negative electrode slurry obtained above was applied to a PET sheet and dried to prepare a negative electrode paste having a density increased to 1.2g/cm by a roll press (manufactured by THANKMETAL)3The electrode of (1). The conductivity of the obtained electrode was measured using a resistivity meter (Loresta-GP, manufactured by mitsubishi chemical Analytech) and the value of comparative example 2 was expressed as an index of 100. A larger index indicates a higher conductivity. The evaluation results are shown in table 2.
[ evaluation of Battery Performance ]
(preparation of Positive electrode for evaluation)
LiNi as a positive electrode active material0.8Co0.15Al0.05O2(NCA)100 parts by mass, 7.8 parts by mass of acetylene black (Li-400, manufactured by DENKA Co., Ltd.) as a conductive aid, 6 parts by mass of polyvinylidene fluoride as a binder, and 61.3 parts by mass of N-methyl-2-pyrrolidone as a dispersion medium were mixed by a planetary mixer to prepare a positive electrode slurry so that the solid content became 65%. Will be provided withThe positive electrode slurry was coated on an aluminum foil 15 μm thick with a coater, dried at 130 ℃ and then subjected to roll-in treatment to obtain a positive electrode active material 22mg/cm2The positive electrode of (1).
[ production of lithium Secondary Battery ]
The positive electrode and the negative electrode obtained above were combined as shown in table 2 below, laminated with a polyolefin (PE/PP/PE) separator as a separator interposed between the electrodes, and the positive electrode terminal and the negative electrode terminal were ultrasonically welded to the respective positive and negative electrodes. The laminate was placed in an aluminum laminate packaging material, and heat-sealed with the opening for injection retained. The area of the anode is 18cm2The area of the negative electrode was 19.8cm2The pre-injection battery of (1). Next, LiPF was injected into a solvent in which ethylene carbonate and diethyl carbonate (in a volume ratio of 30/70) were mixed6(1.0mol/L) of an electrolyte solution, and the opening was heat-sealed to obtain a battery for evaluation.
[ evaluation of Battery Performance ]
The resulting lithium secondary battery was subjected to a performance test at 20 ℃. The test method is as follows. The test results are shown in table 2.
(Charge-discharge cycle characteristics)
The charge-discharge cycle characteristics were measured under the following conditions. The cycle was performed 300 times at 20 ℃ after CC (constant current) charging up to 4.2V at a current density corresponding to 0.5C, followed by switching to CV (constant voltage) charging at 4.2V, CC discharging up to 2.7V at a current density corresponding to 0.5C after 1.5 hours of charging, and the ratio of the 1C discharge capacity to the initial 1C discharge capacity after 300 cycles at this time was set as the 1C charge-discharge cycle retention ratio.
[ Table 2]
Figure BDA0003308533010000201
As is clear from table 2, in the negative electrodes 1 to 8 used in examples 1 to 8, the negative electrode 10 using the fibrous nanocarbon material B' -1 having a short average fiber length had poor conductivity and poor adhesion, and thus the lithium secondary battery shown in comparative example 2 using them had poor charge-discharge cycle characteristics. Further, it is found that the adhesion of negative electrode 20 was also deteriorated by changing the polymer component to sodium polyacrylate, and the charge-discharge cycle characteristics of the lithium secondary battery shown in comparative example 5 using this electrode were also deteriorated.
It is also found that the adhesion of the electrode and the conductivity of the electrode of negative electrode 11 using no fibrous nanocarbon material are deteriorated, and the battery performance of the lithium secondary battery shown in comparative example 3 using this electrode is also significantly deteriorated as compared with the battery performance of examples 1 to 15.
In addition, the coating material properties of the negative electrode 12 in which the nanocellulose fibers are not used in the fibrous nanocarbon dispersion are deteriorated, and the thixotropic property of the electrode coating composition becomes too high for the negative electrode 13 in which the content of the nanocellulose fibers is too large with respect to the fibrous nanocarbon dispersion, so that normal coating cannot be performed, and a uniform electrode cannot be obtained.
Industrial applicability
The binder composition for an electrode of the present invention can be used as a binder for an active material or the like of an electricity storage device, and the electrode produced thereby is used for the production of various electricity storage devices. The obtained power storage device can be used for various portable devices such as mobile phones, notebook personal computers, Personal Digital Assistants (PDAs), video cameras, and digital cameras, and medium-or large-sized power storage devices mounted on electric bicycles, electric vehicles, and the like.

Claims (6)

1. A binder composition for an electrode, characterized in that,
the binder composition for an electrode contains: (A) one or two or more polymer components selected from the group consisting of a fluorine-based polymer, a butadiene-based polymer and a thermoplastic elastomer, (B) a fibrous nanocarbon material having an average fiber diameter of 0.5nm to 20nm and an average fiber length of 0.5 μm to 1mm, (C) a cellulose material, (D) a nanocellulose fiber and (E) water,
the mass ratio of the components (A) to (B) is (A)/(B) 60/40-98/2.
2. The binder composition for an electrode according to claim 1,
the mass ratio of the component (C) to the component (D) is (C)/(D) 30/70-98/2.
3. The electrode coating liquid composition according to claim 1 or 2,
the cellulose material (C) has a viscosity of a 1% by mass aqueous solution (at 25 ℃) of 500 mPas or less.
4. The coating liquid composition for an electrode according to claim 1,
comprising the binder composition for an electrode according to any one of claims 1 to 3, an active material and a dispersant,
the component (A) is 0.1 to 10 mass% based on the solid content of the electrode coating liquid composition,
the component (B) is 0.06 to 2 mass% based on the solid content of the electrode coating liquid composition,
the component (C) is 0.06 mass% or more and 3 mass% or less with respect to the solid content of the electrode coating liquid composition.
5. An electrode for electric storage equipment, characterized in that,
the coating liquid composition for an electrode according to claim 4.
6. An electric storage apparatus is characterized in that,
the battery backup electrode of claim 5 is provided.
CN202080029593.8A 2019-04-22 2020-03-05 Binder composition for electrode, coating composition for electrode, electrode for electricity storage device, and electricity storage device Pending CN113728458A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2019080600A JP6941637B2 (en) 2019-04-22 2019-04-22 Binder composition for electrodes, paint composition for electrodes, electrodes for power storage devices, and power storage devices
JP2019-080600 2019-04-22
PCT/JP2020/009403 WO2020217731A1 (en) 2019-04-22 2020-03-05 Binder composition for electrode, coating composition for electrode, electrode for power storage device, and power storage device

Publications (1)

Publication Number Publication Date
CN113728458A true CN113728458A (en) 2021-11-30

Family

ID=72935920

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202080029593.8A Pending CN113728458A (en) 2019-04-22 2020-03-05 Binder composition for electrode, coating composition for electrode, electrode for electricity storage device, and electricity storage device

Country Status (5)

Country Link
US (1) US20220200003A1 (en)
JP (1) JP6941637B2 (en)
KR (1) KR20210153610A (en)
CN (1) CN113728458A (en)
WO (1) WO2020217731A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114361452A (en) * 2021-12-15 2022-04-15 电子科技大学中山学院 Adhesive, electrode slurry, and manufacturing method and application thereof

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021060322A1 (en) * 2019-09-26 2021-04-01 日本製紙株式会社 Non-aqueous electrolyte secondary cell binder, non-aqueous electrolyte secondary cell electrode composition, non-aqueous electrolyte secondary cell electrode, and non-aqueous electrolyte secondary cell
JP7183212B2 (en) 2020-03-23 2022-12-05 株式会社東芝 SECONDARY BATTERY ELECTRODE, SECONDARY BATTERY, BATTERY PACK, AND VEHICLE
US20230361307A1 (en) * 2020-09-30 2023-11-09 Panasonic Intellectual Property Management Co., Ltd. Secondary battery negative electrode and secondary battery
KR20230108124A (en) * 2022-01-10 2023-07-18 주식회사 한솔케미칼 Nanocellulose-based aqueous binder and slurry for secondary battery electrode

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101207193A (en) * 2006-12-21 2008-06-25 比亚迪股份有限公司 Method for preparation of electrode slurry
CN101847720A (en) * 2005-07-04 2010-09-29 昭和电工株式会社 The method for preparing anode for lithium secondary battery, anode composition and lithium secondary battery
JP2011003529A (en) * 2009-05-21 2011-01-06 Mitsubishi Chemicals Corp Binder resin composition for nonaqueous secondary battery, negative electrode for nonaqueous secondary battery, and nonaqueous secondary battery
CN102483977A (en) * 2009-08-27 2012-05-30 大日精化工业株式会社 Aqueous carbon filler dispersion coating liquid, conductivity-imparting material, electrode plate for an electrical storage device, manufacturing method therefor, and electrical storage device
CN108028358A (en) * 2015-09-30 2018-05-11 日本瑞翁株式会社 Use in electrode for secondary battery conductive material paste composite, slurry for secondary battery electrode composition, use in electrode for secondary battery carry collector, electrode for secondary battery and the secondary cell of priming coat
JP2019016457A (en) * 2017-07-04 2019-01-31 第一工業製薬株式会社 Dispersant for electrode coating liquid, electrode coating liquid composition containing the dispersant for electrode coating liquid, power storage device electrode manufactured by use of the electrode coating liquid composition, and power storage device including the electrode

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5602262B2 (en) * 2013-01-29 2014-10-08 昭和電工株式会社 Composite electrode material
JP2015153714A (en) * 2014-02-19 2015-08-24 三菱マテリアル株式会社 Electrode for lithium ion secondary battery
US10854881B2 (en) 2014-04-21 2020-12-01 Tokyo University Of Science Foundation Binder for lithium cell
JP6849443B2 (en) * 2017-01-17 2021-03-24 株式会社ダイセル Method for manufacturing electrode slurry, method for manufacturing electrodes and secondary batteries
EP3573153A4 (en) * 2017-01-17 2020-01-15 Daicel Corporation Electrode slurry, electrode, manufacturing method thereof, and secondary battery

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101847720A (en) * 2005-07-04 2010-09-29 昭和电工株式会社 The method for preparing anode for lithium secondary battery, anode composition and lithium secondary battery
CN101207193A (en) * 2006-12-21 2008-06-25 比亚迪股份有限公司 Method for preparation of electrode slurry
JP2011003529A (en) * 2009-05-21 2011-01-06 Mitsubishi Chemicals Corp Binder resin composition for nonaqueous secondary battery, negative electrode for nonaqueous secondary battery, and nonaqueous secondary battery
CN102483977A (en) * 2009-08-27 2012-05-30 大日精化工业株式会社 Aqueous carbon filler dispersion coating liquid, conductivity-imparting material, electrode plate for an electrical storage device, manufacturing method therefor, and electrical storage device
CN108028358A (en) * 2015-09-30 2018-05-11 日本瑞翁株式会社 Use in electrode for secondary battery conductive material paste composite, slurry for secondary battery electrode composition, use in electrode for secondary battery carry collector, electrode for secondary battery and the secondary cell of priming coat
JP2019016457A (en) * 2017-07-04 2019-01-31 第一工業製薬株式会社 Dispersant for electrode coating liquid, electrode coating liquid composition containing the dispersant for electrode coating liquid, power storage device electrode manufactured by use of the electrode coating liquid composition, and power storage device including the electrode

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114361452A (en) * 2021-12-15 2022-04-15 电子科技大学中山学院 Adhesive, electrode slurry, and manufacturing method and application thereof
CN114361452B (en) * 2021-12-15 2023-09-19 电子科技大学中山学院 Adhesive, electrode slurry, and manufacturing method and application thereof

Also Published As

Publication number Publication date
US20220200003A1 (en) 2022-06-23
JP2020177849A (en) 2020-10-29
JP6941637B2 (en) 2021-09-29
WO2020217731A1 (en) 2020-10-29
KR20210153610A (en) 2021-12-17

Similar Documents

Publication Publication Date Title
JP6716288B2 (en) Lithium-ion battery electrode, lithium-ion battery, and method for manufacturing lithium-ion battery electrode
JP6183361B2 (en) Negative electrode active material, method for producing the same, negative electrode for lithium secondary battery, and lithium secondary battery
JP6941637B2 (en) Binder composition for electrodes, paint composition for electrodes, electrodes for power storage devices, and power storage devices
CN107429009B (en) Conductive composition and method for producing same, collector with base layer for electricity storage device, electrode for electricity storage device, and electricity storage device
KR102194750B1 (en) Multi-shell Anode Active Material, Manufacturing Method thereof and Lithium Secondary Battery Comprising the Same
JP2016506055A (en) Cathode active material for lithium-sulfur battery and method for producing the same
US20150016024A1 (en) Cathode active material having core-shell structure and producing method thereof
JP2016219410A (en) Negative electrode active material for secondary battery, production method of negative electrode active material for secondary battery, negative electrode for lithium ion secondary battery, and lithium ion secondary battery
JP2016192398A (en) Conductive composition, collector with underlying for power storage device, electrode for power storage device, and power storage device
JP2014022039A (en) Negative electrode binder for lithium secondary battery
JP2016219408A (en) Negative electrode active material for secondary battery, production method of negative electrode active material for secondary battery, negative electrode for lithium ion secondary battery, and lithium ion secondary battery
JP6808948B2 (en) Negative electrode for non-aqueous lithium-ion secondary battery, its manufacturing method and non-aqueous lithium-ion secondary battery
CN113692661A (en) Binder for lithium secondary battery electrode, positive electrode for lithium secondary battery comprising same, and lithium secondary battery
JP2008251523A (en) Negative electrode material for nonaqueous electrolyte secondary battery, negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery
JP5200329B2 (en) Electrode plate for non-aqueous electrolyte secondary battery, method for producing the same, and non-aqueous electrolyte secondary battery
JP2023520194A (en) Negative electrode and secondary battery containing the same
JP2008198536A (en) Electrode, and secondary battery or capacitor using it
KR101776989B1 (en) Slurry composition for anode and its fabrication method
JP2017228344A (en) Conductive composition, backing-attached current collector for power storage device, electrode for power storage device, and power storage device
JP2020077620A (en) Binder composition for electrochemical device
JP6844236B2 (en) Manufacturing method of carbonaceous material
JP2011181387A (en) Manufacturing method of electrode mixture for electrochemical element
WO2003056653A1 (en) Nonaqueous electrolyte secondary cell
CN115152048A (en) Negative electrode for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery
JP6874283B2 (en) Conductive compositions, grounded current collectors for power storage devices, electrodes for power storage devices, and power storage devices

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination